Ukrainian lawmakers have voted to submit draft bills to the country's top court​ that would enshrine Ukraine’s course toward Euro-Atlantic integration in the constitution.

A total of 321 lawmakers voted on September 20 to appeal to the Constitutional Court to review the proposed amendments.

After the court issues its judgment, the draft bills will return to the Verkhovna Rada where they will need at least 300 votes to pass.

Earlier in the day, President Petro Poroshenko told lawmakers that Ukraine needs the constitutional amendments to make EU and NATO membership its long-term goal.

In his annual address to parliament on Ukraine's domestic and foreign policy, Poroshenko said the Ukrainian armed forces will meet the criteria for NATO membership by 2020.

The move comes amid continued fighting between Ukrainian government forces and Russia-backed separatists in a conflict that has killed more than 10,300 in eastern Ukraine since April 2014.

Peace accords signed in Belarus’s capital, Minsk, in September 2014 and February 2015, have failed to put an end to the fighting.

Moscow's support for the separatists and its seizure of Ukraine's Crimean Peninsula in March 2014 prompted the United States, the European Union, and others to impose sanctions on Russia.

In his speech, Poroshenko warned that there was a risk of the international sanctions imposed on Russia for its actions in Ukraine being eased.

"We will consistently oppose attempts to ease the sanctions pressure on Russia," he said. "But know that there is a risk of softening [sanctions]."

Making concessions to Russia before it had handed the Crimean Peninsula back to Ukraine would be a defeat for international law, the president added.

As Poroshenko delivered his address, four people were reported injured in clashes between police officers and demonstrators outside the parliament building. At least one police officer was taken to hospital.

The demonstrators were calling for a relaxation of the rules on gaining Ukrainian citizenship for foreigners who have fought for Ukraine against the separatists in the country’s east.